(1) Field of the Invention
The present invention relates to an improvement on a harness fixing device for holding a wiring harness rotatably in the circumferential direction on a vehicle body or slide door of a motor vehicle.
(2) Description of the Related Art
FIG. 8 is a perspective view illustrating an example of usage of a conventional harness fixing device.
A harness fixing device 76 fixes a wiring harness 73 on a vehicle body or the like. A plurality of electric wires 72 are covered with a corrugated tube 71, thereby the wiring harness 73 is constructed. The corrugated tube 71 is made of synthetic resin and formed in a thin cylindrical shape, in which a concave groove and convex strip, each extending in a circumferential direction, are alternately arranged in parallel with a constant pitch in the longitudinal direction of the tube. The corrugated tube 71 is flexible.
The corrugated tube 71 functions as a tube for protecting wires and easily bends together with a plurality of wires 72 according to a panel 75 curved into a two or three dimensional shape of a mounting side 74 of a vehicle body or the like, thereby improving a feasibility of arrangement of the wiring harness 73.
The corrugated tube 71 may or may not have a slit in the longitudinal direction. As for the corrugated tube 71 having a slit, the wires 72 can be easily inserted inside the corrugated tube 71 from the slit. As for the corrugated tube 71 having no slit, the insertion work of the wires 72 into the corrugated tube 71 is time-consuming, however on the other hand, there is no possibility of the slit opening and there is no need of wrapping up with a vinyl tape to prevent the slit from opening.
For example, the harness fixing device 76 is constituted as a clamp for pressing the corrugated tube 71 onto the panel 75 of the mounting side 74. The harness fixing device 76 is invariably arranged at least at the bending portion of the mounting side 74 of a vehicle body or the like. A bundling tool such as a band can be used as the harness fixing device.
The harness fixing device 76 is fixed on the panel 75 of the mounting side 74 with a flexible locking clip or machine screw. The locking clip (not shown in the figure) has a pair of flexible locking pieces and is inserted into and locked by a hole of the panel 75. When a machine screw (not shown) is used, the machine screw is inserted into a hole of a bracket of the harness fixing device 76 and screwed into a tapped hole of the panel 75, thereby the harness fixing device 76 is fixed on the panel 75.
The wiring harness 73 is arranged along a curved surface of the mounting side 74 of a vehicle body or the like and the outside corrugated tube 71 is firmly fixed to the mounting side 74 with a plurality of harness fixing devices 76 arranged in the longitudinal direction of the tube. Thereby, the wiring harness 73 is firmly fixed to the mounting side 74 and for example, the shake due to the vibration upon traveling of a vehicle or the interaction between a vehicle body (the mounting side 74) and the wiring harness 73 and the noise due to the interaction can be prevented from occurring.
The wires 72 in the corrugated tube 71 are protected from rainwater and dust by the corrugated tube 71. The wires 72 are extended up to a specific portion such as an instrument panel, floor and door (hinge-type or slide-type door) along a vehicle body (74) and connected to the electric equipment or auxiliary through a connector.
However, as for a conventional harness fixing device 76 described above, when the corrugated tube 71 is firmly fixed with the harness fixing device 76 in order to fix the wiring harness 73 to the bending position of the mounting side 74 having a three-dimensional shape of a vehicle body or the like, the wires 72 and corrugated tube 71 are bent and twisted. This twist stress affects the corrugated tube 71, causing a problem of the deformation or damage of the corrugated tube 71 or a problem of the opening of the slit. When the slit is opened, the inside wires 72 might stick out outside and might be trodden on by a foot, and water or dust might enter inside from the opening.
Further, since the corrugated tube 71 receives a tensile force, the corrugated tube 71 rubs against an end portion of the harness fixing device, possibly causing wear or damage. When the wiring harness 73 is bent on a large scale to be arranged or the wiring harness 73 is shaken on a large scale having the harness fixing device 76 as a fulcrum, the wiring harness 73 including the corrugated tube 71 easily be bent or rubbed at the opening portion from which the corrugated tube 71 is guided out, causing possible damage of the corrugated tube 71 or the inside wires 72.
In the above explanation, a corrugated tube is used as a tube for protection. Instead, for example, when a net-shaped tube made of synthetic resin or a vinyl tape is used as the tube for protection, the same problems as described above can be arisen.
It is therefore an objective of the present invention to solve the above problems and to provide a harness fixing device, by which the twist of the tube for protection and the rubbing or damage of the tube and wires can be securely prevented from occurring when the wiring harness is arranged to be fixed, bent or shaken.
In order to attain the above objective, the present invention is to provide a harness fixing device comprising: a rotatable member for holding a wiring harness; and a fixing device body for holding the rotatable member rotatably in the circumferential direction, wherein the rotatable member is provided with a harness guiding wall having a curved shape and the harness guiding wall is rotatable integrally with the wiring harness.
With the construction described above, when the wiring harness is bent, the rotatable member rotates integrally with the wiring harness, thereby the harness guiding wall rotates integrally with the wiring harness. Consequently, no rubbing takes place between the harness guiding wall and wiring harness. The wiring harness bends in a curved shape along the harness guiding wall. The wiring harness is prevented from being excessively bent or receiving an excessive bending stress. The wiring harness is located inside the harness guiding wall and protected from the interaction with the outside. The wiring harness is prevented from being worn or damaged. Since the wiring harness rotates integrally with the rotatable member, the wiring harness is prevented from being twisted.
Preferably, the rotatable member is movable in the longitudinal direction of the harness in the fixing device body simultaneously with the rotation.
With the construction described above, the rotatable member moves in the longitudinal direction in the fixing device body in response to the bending or shaking of the wiring harness. When the rotatable member advances, the wiring harness protrudes forward long and curves on a large scale with a largely curved radius along the harness guiding wall. Consequently, the wiring harness is protected from an excessive bending stress and a sufficient gap with a vehicle body is secured, thereby preventing an interaction between the wiring harness and the outside such as a vehicle body or the like from occurring.
Preferably, the harness guiding wall is formed over the whole circumference of the rotatable member.
With the construction described above, even when the wiring harness is shaken or bent in any direction, the harness guiding wall always holds the wiring harness in a smoothly curved shape. Thereby, the wiring harness is securely prevented from being excessively bent or receiving an excessive bending stress.
Preferably, an inner surface of the harness guiding wall is flush with an inner surface for holding the harness of the rotatable member.
With the construction described above, the outer circumferential surface of the wiring harness uniformly comes in contact with from the inner surface for holding the harness of the rotatable member up to the inner surface of the harness guiding wall without any step or gap. Consequently, the wiring harness is bent in a smoothly curved shape without suffering from an excessive bending, thereby the wiring harness is securely prevented from being excessively bent or receiving an excessive bending stress.
Preferably, the rotatable member has a portion for holding a corrugated tube of the wiring harness.
With the construction described above, the corrugated tube situated at the outer circumferential side of the wiring harness is held immovably by the rotatable member and the wires in the corrugated tube are relatively freely rotatable in the corrugated tube, thereby the wires are protected from being excessively affected by the twisting force or bending force when the wiring harness is bent. Consequently, the wires are prevented from being damaged. The corrugated tube is bent in a curved shape along the harness guiding wall. Since the harness guiding wall rotates integrally with the rotatable member and the corrugated tube, the harness guiding wall is prevented from suffering from the twist with the corrugated tube, thereby the corrugated tube is prevented from being worn or damaged.